1. Field of the Invention
The present invention relates to a micro switch and, more particularly, to a low voltage micro switch capable of being driven at a low voltage, accurately controlling ON/OFF, and facilitating processes and integration with a circuit part.
2. Description of the Background Art
Electronic systems used at a high frequency band are becoming ultra-compact, ultra-light and better in performance. Accordingly, in the existing electronic system, researches are ongoing on a micro switch using a new technology called a micromachining as a substitute for a semiconductor switch such as an FET (Field Effect Transistor) or a pin diode.
The conventional semiconductor switches have problems in that their power loss is high, there is a distortion and nonlinearity, and ON/OFF insulation is not completely made.
Researches are widely ongoing toward implementing micro switches such as a MEMS switch or a tunable capacitor by employing an actuator which is fabricated by using the micromachining technology and has mechanical motion.
The micro switches can be applied to next-generation mobile communication terminals, personal digital assistance (PDA), wireless communication systems, phase shifters, antenna tuners, receivers, transmitters, phase arrayed smart antennas, satellite broadcasters, satellite communicators or the like, and as such it is highly expected to accomplish compact, light, high-performance and low-priced electronic systems.
Most of micro switches, such as the MEMS switches and the tunable capacitor, which have been developed and proposed to date employs the actuator operated by an electrostatic force or a magnetic force.
Even though the MEMS switch and the tunable capacitor driven by the electrostatic force have such a low power consumption as to be neglected, they are disadvantageous in terms of reliability that a stiction problem occurs due to charging and microwelding when they are driven.
Meanwhile, referring to the MEMS switch and the tunable capacitor driven by the magnetic force, even through they can be driven at a low voltage, their power consumption is quite high and their fabrication process is complicate, and in addition, because it is difficult to integrate them together with other integrated circuit device on a single chip, a size of a system can not be much reduced.
Therefore, a micro switch, that can be driven at a low voltage, have a high reliability and can be integrated together with other integrated circuit on a single substrate, is required.